Convert all instances of "exit 2" to simply "exit 1"

See https://github.com/docker/docker/pull/24856 for more details.

cassandra/docker-healthcheck

@@ -7,6 +7,4 @@ if cqlsh -u cassandra -p cassandra "$host" < /dev/null; then
 	exit 0
 fi
 
-# If the probe returns 2 ("starting") when the container has already moved out of the "starting" state then it is treated as "unhealthy" instead.
-# https://github.com/docker/docker/blob/dcc65376bac8e73bb5930fce4cddc2350bb7baa2/docs/reference/builder.md#healthcheck
-exit 2
+exit 1

elasticsearch/docker-healthcheck

@@ -11,6 +11,4 @@ if health="$(curl -fsSL "http://$host:9200/_cat/health?h=status")"; then
 	echo >&2 "unexpected health status: $health"
 fi
 
-# If the probe returns 2 ("starting") when the container has already moved out of the "starting" state then it is treated as "unhealthy" instead.
-# https://github.com/docker/docker/blob/dcc65376bac8e73bb5930fce4cddc2350bb7baa2/docs/reference/builder.md#healthcheck
-exit 2
+exit 1

mongo/docker-healthcheck

@@ -7,6 +7,4 @@ if mongo --quiet "$host/test" --eval 'quit(db.runCommand({ ping: 1 }).ok ? 0 : 2
 	exit 0
 fi
 
-# If the probe returns 2 ("starting") when the container has already moved out of the "starting" state then it is treated as "unhealthy" instead.
-# https://github.com/docker/docker/blob/dcc65376bac8e73bb5930fce4cddc2350bb7baa2/docs/reference/builder.md#healthcheck
-exit 2
+exit 1

mysql/docker-healthcheck

@@ -22,6 +22,4 @@ if select="$(echo 'SELECT 1' | mysql "${args[@]}")" && [ "$select" = '1' ]; then
 	exit 0
 fi
 
-# If the probe returns 2 ("starting") when the container has already moved out of the "starting" state then it is treated as "unhealthy" instead.
-# https://github.com/docker/docker/blob/dcc65376bac8e73bb5930fce4cddc2350bb7baa2/docs/reference/builder.md#healthcheck
-exit 2
+exit 1

postgres/docker-healthcheck

@@ -16,6 +16,4 @@ if select="$(echo 'SELECT 1' | psql "${args[@]}")" && [ "$select" = '1' ]; then
 	exit 0
 fi
 
-# If the probe returns 2 ("starting") when the container has already moved out of the "starting" state then it is treated as "unhealthy" instead.
-# https://github.com/docker/docker/blob/dcc65376bac8e73bb5930fce4cddc2350bb7baa2/docs/reference/builder.md#healthcheck
-exit 2
+exit 1

rabbitmq/docker-healthcheck

@@ -8,6 +8,4 @@ if rabbitmqctl status; then
 	exit 0
 fi
 
-# If the probe returns 2 ("starting") when the container has already moved out of the "starting" state then it is treated as "unhealthy" instead.
-# https://github.com/docker/docker/blob/dcc65376bac8e73bb5930fce4cddc2350bb7baa2/docs/reference/builder.md#healthcheck
-exit 2
+exit 1

redis/docker-healthcheck

@@ -7,6 +7,4 @@ if ping="$(redis-cli -h "$host" ping)" && [ "$ping" = 'PONG' ]; then
 	exit 0
 fi
 
-# If the probe returns 2 ("starting") when the container has already moved out of the "starting" state then it is treated as "unhealthy" instead.
-# https://github.com/docker/docker/blob/dcc65376bac8e73bb5930fce4cddc2350bb7baa2/docs/reference/builder.md#healthcheck
-exit 2
+exit 1